This video I did a couple of years on needing a baby pin to make a C-Stand work correctly generated a lot of discussion and questions, so I am trying to answer most of your questions in this video.

Links to Avenger E250 long baby pin:

B&H: https://www.bhphotovideo.com/c/produc...

Adorama: https://www.adorama.com/aee250.html?o...

Other sites: Just search "Avenger E250" for query results.